The California Scrub Jay is among the most intelligent of animals: the only non-primate or non-dolphin shown to plan ahead for the future (known as metacognition), which was previously thought of as a uniquely human trait.
“Among the most intelligent of animals” - Wikipedia.
“… the malaprop, the impertinent, the sly wag, thief, scoundrel, outcast, jackal of the bush, bon homme libre, as innocent as morning, as industrious as noon, as wicked as night. C'est le dernier des oiseaux.” - W. Leon Dawson, “The Birds of California” (1923)
“A jay hasn’t got any more principle than a Congressman. A jay will lie, a jay will steal, a jay will deceive, a jay will betray; and four times out of five, a jay will go back on his solemnest promise.” - Mark Twain, “Jim Baker's Blue-Jay Yarn”, 1865.
“Thieves, every one of them.” - Acorn Woodpeckers, whose granaries are frequent targets of California Scrub-Jay robberies.